1/3 Octave Band Chamber Type Anechoic chambers are commonly used in f loor that acts as a work surface for Frequency( Hz) Tolerance (dB) acoustics to conduct experiments in nominally supporting heavy items, such as cars, "free field" condi- tions. All sound energy will washing machines, or industrial machinery, ≤ 630 ± 1.5 Anechoic be traveling away from the source with almost rather than the mesh floor grille over 800-5,000 ± 1.0 Chamber none reflected back. Common anechoic absorbent tiles found in full anechoic ≥6,300 ± 1.5 chamber experiments include measuring chambers. This floor is damped and floating Semi- ≤ 630 ± 2.5 the transfer function of a loudspeaker or the on absorbent buffers to isolate it from outside Anechoic 800-5,000 ± 2.0 Chamber directivity of noise radiation from industrial vibration or electromagnetic signals. A ≥6,300 ± 2.5 machinery. In general, the interior of an recording studio may utilize a semi-anechoic anechoic chamber is very quiet, with typical chamber to produce high-quality music, free noise levels in the 10–20 dBA range. Full of outside noise and unwanted echoes. anechoic chambers aim to absorb energy in Semi- all directions. Semi-anechoic chambers have Anechoic a solid